Worsening of physical fitness caused by aging manifests itself in the symptoms of fatigue. A vicious cycle takes place in which fatigue causes lack of physical activity, which, in turn, induces the loss of muscle strength. The loss of muscle strength may cause bone fractures due to falling or may result in a bedridden condition. Therefore, in order to enjoy a fruitful and comfortable old age, it is important to relieve fatigue and to prevent the loss of muscle strength as much as possible.
In the past, many agents for recovery from fatigue have been marketed. However, most of these agents have been prescribed as stimulants for young persons or young athletes, and there were none that middle-aged and older persons could use safely for continuously over a long period of term to maintain health and physical fitness.
Coenzyme Q is an essential component and distributed widely in living organisms from bacteria to mammals. In humans, it is known that coenzyme Q10, which is coenzyme Q with 10 repeated units in the side chain, is the main component. Coenzyme Q10 is a physiological component present as a constitutive component of the electron transport system of the mitochondria in cells of living organisms and functions as a transport component of the electron transport system by repeating oxidation and reduction in the living organism. Coenzyme Q is known to show activities in energy production, membranestabilization, andantioxidation, andusefulwidely. The oxidized coenzyme Q10 (ubiquinon or ubidecarenon) has been known to act effectively on the heart, and it has been used in pharmaceutical application as an agent for congestive heart failure. Its effects on improving the oxygen availability in the heart muscle, activation of ATP production in the heart muscle, improvement on heart functions and the like, have been reported. Other than for the pharmaceutical application, its effects as a nutrient and a nutritional supplement, like vitamins, have been reported. Further, Japanese Patent Laid-Open No. 62-59208 reports a composition for activating tissue metabolism comprising a mixture of the oxidized coenzyme Q10 (ubiquinon) and dried yeast powder, Japanese Patent Laid-Open No. 52-99220 reports improvements in symptoms of myasthenia gravis using the oxidized coenzyme Q10, and Japanese Patent Laid-Open No. 52-99222 reports increased red blood cell counts using the oxidized coenzyme Q10. Still further, its effect of recovery from fatigue using the oxidized coenzyme Q10 has been reported (Japanese Patent Laid-Open No. 7-330584, Japanese Patent Laid-Open No. 7-330593 and Japanese Patent Laid-Open No. 10-287560).
Unlike oxidized coenzyme Q10, however, there has been no report as to the usefulness of reduced coenzyme Q10. This is due to the fact that since reduced coenzyme Q10 is readily oxidized by air, its usefulness could not be evaluated. Another reason why the usefulness of reduced coenzyme Q10 has not been evaluated is that the effects of oxidized coenzyme Q10 and reduced coenzyme Q10 on the living organisms are considered to be equivalent because, it is known that reduced coenzyme Q10 increases in general, due to reduction in living organisms even following administration of oxidized coenzyme Q10. We have disclosed earlier in Japanese Patent Laid-Open No. 10-109933 that the oral absorption of coenzyme Q10 is increased when both oxidized coenzyme Q10 and reduced coenzyme Q10 coexist as compared to when oxidized coenzyme Q10 alone exists. We showed that the use of reduced coenzyme Q10 is very effective in increasing the oral absorption for various applications. However, there has been no information on whether or not there is any difference in anti-fatigue effect between oxidized coenzyme Q10 and reduced coenzyme Q10.
The objective of the present invention is to develop a composition which is effective for reducing and preventing physical fatigue and which is safe for continuous and long-term administration in middle-aged and older persons.